The present invention relates generally to fiber optic closures and, more particularly, to closures having an internal frame for appropriately organizing and routing optical fibers and/or electrical connectors within the closure.
Fiber optic networks typically include closures at various splice locations throughout the fiber optic network. Typically, these closures include splice closures, patch closures and the like. For example, splice closures commonly house the splices required to connect the optical fibers of one or more fiber optic feeder cables to. respective ones of the optical fibers of a fiber optic drop cable. By housing the splices, a splice closure protects the spliced end portions of the optical fibers from environmental degradation, strain and other deleterious forces, thereby increasing the reliability and quality of the splices.
While fiber optic networks have traditionally served as the backbone or trunkline of communication networks so as to transmit signals over relatively long distances, fiber optic networks are gradually being extended closer to the end points of the communications networks. In this regard, fiber optic networks have been developed that deliver fiber-to-the-curb (FTTC), fiber-to-the-home (FTTH); fiber-to-the-desk and the. like. In each of these different applications, a splice closure must be capable of splicing different types of cables in order to establish the proper interconnections. In this regard, the splice closure utilized in a FTTH application is adapted to interconnect a fiber optic feeder cable and one or more fiber optic drop cables so as to permit at least some of the optical fibers of the feeder cable to extend uninterrupted through the splice closure while splicing or otherwise connecting the other optical fibers of the fiber optic feeder cable with optical fibers of the one or more drop cables. In contrast, a splice closure that is utilized in a FTTC application is adapted to interconnect not just a fiber optic feeder cable and one or more drop cables, but also an electrical feeder cable. In the FTTC application, the splice closure must facilitate the splicing of one or more electrical conductors of the electrical feeder cable to corresponding electrical conductors of the one or more drop cables, while permnitting the remainder of the electrical conductors of the electrical feeder cable to extend uninterrupted through the closure. Additionally, the splice closure must facilitate the splicing of one or more of the optical fibers of the fiber optic feeder cable with respective optical fibers of the one or more drop cables while continuing to permit at least some of the optical fibers of the fiber optic feeder cable to extend uninterrupted through the splice closure.
Currently, different types of splice closures are provided for FTTH and FTTC applications. While effective for providing the necessary splice.connections, both types of splice closures must be manufactured and maintained in stock. In addition, field technicians must be trained to install and service each type of splice closure.
Within either type of splice closure, that is, a splice closure for a FTTH application or a splice closure for a FTTC application, it is oftentimes relatively difficult to separate the express optical fibers that extend uninterrupted through the splice closure from the optical fibers that are spliced to the optical fibers.of the drop cables. In this regard, the express optical fibers and the optical fibers that are spliced to the drop cables are oftentimes routed and stored in a common manner. Therefore, in instances in which the splice closure must be reconfigured so as to provide additional or different splice connections, it may be relatively difficult and time consuming to separate the express optical fibers and the optical fibers of the drop cables to identify the particular optical fibers which must now be interconnected.
In addition to identifying respective ones of the optical fibers, a field technician must generally access the splice tray or connector panel in order to change the interconnections between the optical fibers or to add additional interconnections between the optical fibers. Unfortunately, however, the field technician must oftentimes access or otherwise work with other portions of the splice closure in order to obtain access to the splice tray or connector panel or to identify the optical fibers to be interconnected. While the field technician will likely be quite familiar with the organization of the splice tray or connector panel, the technician may be much less familiar with the other portions of the splice closure. As such, the other portions of the splice closure may be inadvertently damaged during the process of accessing the splice tray or connector panel, or in the process of identifying the optical fibers to be interconnected. Moreover, even if a field technician is careful not to damage other portions of the splice closure, the technician will typically require more time to access the splice tray or connector panel and make the appropriate interconnections in those instances in which the technician must first access or otherwise work with other portions of the splice closure.
As such, while splice closures have been developed for various applications including FTTH and FTTC applications, it would still be desirable to develop a splice closure that could be installed, service and reconfigured in a more efficient manner. In this regard, it would be desirable to have a splice closure that is universally adapted for use in both FTTH and FTTC applications to reduce the number of different types of splice closures that must be manufactured and maintained in stock and to reduce the number of splice closures with which a field technician must be familiar. Moreover, it would be desirable to develop a well organized splice closure in which the express optical fibers and the optical fibers that are spliced to the optical fibers of the drop cables, as well as any electrical conductors, are separately routed and stored in order to facilitate subsequent reconfiguration of the spice closure in a manner that is efficient and is relatively straight-forward for the technician, and thereby avoid inadvertent damage to other portions of the splice closure.
A fiber management frame and a closure including the fiber management frame are provided that are adapted to be utilized in a universal manner for both FTTH and FTTC applications. Moreover, the fiber management frame of the present invention is designed to separately route and store express optical fibers that extend uninterrupted through the closure and optical fibers that are to be spliced to optical fibers of one or more drop cables and, in FTTC applications, electrical conductors of an electrical feeder cable that are to be connected to electrical conductors of one or more composite drop cables. As such, the fiber management frame and the associated closure of the present invention will facilitate installation and service, as well as any subsequent reconfiguration of the closure.
According to one aspect of the present invention, a closure is provided that includes a housing defining a lengthwise extending internal cavity and further defining a plurality of ports opening into the internal cavity for receiving a plurality of feeder and drop cables. Typically, the housing defines ports for receiving a fiber optic feeder cable and at least one drop cable and, in FTTC applications, an additional port for receiving an electrical feeder cable. The closure also includes a fiber management frame disposed within the internal cavity defined by the housing. The fiber management frame includes a back panel attached to the housing and four separate compartments for appropriately separating and routing optical fibers and, in FTTC applications, electrical conductors.
In this regard, the first compartment preferably includes a partition that extends both outwardly from the back panel and in a lengthwise direction. The first compartment therefore extends lengthwise from a first open end to a second open end. In one aspect of the present invention, such as in FTTH applications, the first compartment receives express optical fibers of the fiber optic feeder cable that extend uninterrupted through the closure. In another aspect of the present invention, such as in FTTC applications, the first compartment is adapted to receive at least one electrical conductor of the electrical feeder cable. In either instance, the first compartment of the fiber management frame may include a cover to protect the express optical fibers or the electrical conductors extending therethrough. The first compartment may also include an angled ramp projecting outwardly from at least one end thereof as well as at least one upturned flange on an edge of the partition opposite the back panel to guide the express optical fibers or the electrical conductors into and to maintain them within the first compartment.
The second compartment is proximate the first compartment and preferably includes a partition that is spaced apart from the partition of the first compartment. Like the partition of the first compartment, the partition of the second compartment extends both outwardly from the back panel and in a lengthwise direction. In addition, the compartment defines at least a first open end. In one aspect of the present invention, such as in FTTH applications, the second compartment stores at least one coupler tray that is adapted to split a first optical fiber of the fiber optic feeder cable into a plurality of second optical fibers. As such, the second compartment may include an engagement member for engaging the at least one coupler tray. Moreover, the partition of the first compartment may define an opening to facilitate access to the second compartment and, more particularly, to the at least one coupler tray stored within the second compartment. According to another aspect of the present invention, such as in FTTC applications, the second compartment is adapted to receive express optical fibers of the fiber optic feeder cable that extend uninterrupted through the closure. The second compartment may also include at least one upturned flange on an edge of the partition opposite the back panel.
The third compartment of the fiber management frame also preferably extends in a lengthwise direction alongside the second compartment from a first open end to a second open end. The third compartment is adapted to store slack lengths of the second optical fibers and/or slack lengths of the optical fibers of the drop cables. In one embodiment, the third compartment therefore includes a plurality of retainers attached to the partition of the second compartment for retaining slack lengths of the second optical fibers and/or optical fibers of the drop cables.
The fourth compartment is proximate the third compartment and preferably comprises a partition that is spaced apart from the partitions of the first and second compartments and that extends both outwardly from the back panel and in the lengthwise direction. Additionally, the fourth compartment defines at least a first open end through which optical fibers may enter and exit. The fourth compartment is adapted to store at least one of either a splice tray or a connector panel, or both. In either instance, the fourth compartment is adapted to interconnect an optical fiber of the fiber optic feeder cable, such as one of the second optical fibers provided by the coupler tray, to a respective optical fiber of a drop cable.
The fiber management frame, as well as a closure incorporating the fiber management frame, may be utilized in a variety of applications, including both FTTH and FTTC applications, thereby reducing the number of different types of closures that must be manufactured and maintained in stock and similarly reducing the number of different closures with which a field technician must be familiar. Additionally, the fiber management frame of the present invention provides for separate routing and storage of the express optical fibers and the optical fibers of the drop cables and, in FTTC applications, the electrical conductors of an electrical feeder cable. Thus, a closure that includes the fiber management frame of the present invention may be serviced and reconfigured in a more efficient manner. Additionally, since the splice tray or connector panel may be accessed without accessing or otherwise working with other portions of the closure, the closure may be serviced or reconfigured in a manner that is less likely to damage the other portions of the closure.